Introduction
TRST series tank type AC resonant test systems are designed for high capacitance load, special for XLPE power cables. There are variable frequency type (mainly used for XLPE cables field test) and variable inductance type (mainly for factory routine test).
TRST series tank type reactors are situated in an enclosed and earthed metal tank and filled with transformer insulation oil inside, additional voltage taps are possible, the output voltage is fed out through the tap-changers by HV bushings. These reactors extend application range, and satisfy testing for cables of various voltage classes.
Application
AC resonant test systems are mainly used to output AC voltage for high voltage routine, type and development testing of capacitive test objects. These systems exert the principle of series resonance, as per f=1/2π√LC, the connection of HV reactors (inductance L) to a capacitive loads (capacitance C) form an oscillating circuit with the frequency (f) of power supply.
Compared to conventional AC test transformers, the relatively lower power required (1/Q), smaller dimension and lighter weight favor these systems as the most practical for field testing, and large capacitance loads.
Principle
Series resonant circuit consists essentially of an inductor in series with a capacitive test object or load connected to a medium-voltage power source. Alternatively it may consist of a capacitor in series with an inductive test object. By varying the circuit parameters or the supply frequency, the circuit can be tuned to resonance, when a voltage considerably greater than that of the source and of substantially sinusoidal shape is applied to test object.
The stability of the resonance conditions and of the test voltage depends on the stability of the supply frequency and of the test system characteristic, described by the quality factor, which is the ratio between test reactive power and power loss.
When a discharge occurs, the circuit capacitance discharges instantaneously and then follow-through current from the source is relatively low. The limit follow-through current generally results in less damage to the test object.
Company Information
We are the leading and earliest manufacturer of high voltage, high current and high power test system in China, provide AC, DC, impulse testing and associated measuring equipment used to electrical application, such as testing project of power cables, power transformers, GIS switchgears, insulators, generators, arresters and etc. And test systems for laboratory, factory and field use are available.
Our factory was founded in 1970, and established R&D center institute of HV testing equipments in 1986, which cooperated with Shanghai Jiaotong University.
We are pleased to announce our quality management system has been approved to ISO 9001 : 2008, so far we have applied more than 58 invention patents.
We have well cooperated with many world famous electrical corporations, like ABB, ALSTOM, SIEMENS, TOSHIBA, HITACHI, HYUNDAI, AE POWERS and etc, also state grids, research institutes, universities and HV testing service providers, we have successfully offered them plenty of high voltage test systems, all well performed.
Our new factory is under construction, which will go into service in 2015, it will become the biggest manufacturer of high voltage testing equipment all over the world.